Effect of Oral Calcium Administration on Metabolic Status and Uterine Health of Dairy Cows With Reduced Postpartum Rumination and Eating Time

BackgroundHypocalcemia has detrimental effects on health and performance of dairy cows. As hypocalcemic cows show reduced feed intake, we hypothesized that cows with lower rumination and eating time (CRET) may benefit from Ca supplementation. The objective was to evaluate the effect of postpartum oral Ca administration on metabolic status (Ca, fatty acids [FA], and β-Hydroxybutyrate [BHB] serum concentrations) and incidence of puerperal metritis (PM) in dairy cows with reduced postpartum CRET. Cows diagnosed with reduced CRET (<489 min/d; n=88) during the first day postpartum were assigned into 1 of 2 treatments: i) Calcium administration (CA; =45) that received 1 Ca oral capsule (Bovikalc bolus, Boehringer Ingelheim, St. Joseph, MO) containing CaCl2 and CaSO4 (43 g of Ca) once per day, for 3 consecutive days, starting at d 1 postpartum; and ii) Control (CON; n=43) that did not receive oral Ca. A convenience group consisting of cows with CRET ≥489 min/d was used for comparison and did not receive oral Ca (NOR; n=96).ResultsAt day 1 postpartum cows with lower CRET had lower Ca serum concentrations (CA=2.08 mmol/L; CON=2.06 mmol/L) compared with NOR cows (2.17 mmol/L). Calcium concentrations at d 3, 5, and 12 postpartum were not different among the three groups. Serum FA concentrations at d 1, 3 and 5 postpartum were higher in both CA and CON cows compared with NOR. At d 12, only CA cows had higher FA concentrations than NOR cows. Serum BHB concentrations at d 3 were highest in CA, with no difference between CON and NOR. At d 5, BHB concentrations were higher in CA, followed by CON, and NOR. No effect was observed for Ca administration on incidence of PM and reproductive performance. CON cows had lower survival at 30 DIM (86.5%) than NOR cows (97.9%).ConclusionsCows with reduced CRET during the first day postpartum had lower Ca concentration and altered metabolic status following parturition. Oral calcium administration did not affect incidence of metabolic disorders nor reproductive health and subsequent pregnancy. Compared with normal cows, survival at 30 days in milk was lower for non-Ca supplemented cows with CRET.